The present invention relates to a wheelchair vehicle and more specifically, to a wheelchair vehicle capable of climbing up or down stairs.
Vehicles capable of negotiating a flight of stairs are known. Such vehicles are generally configured to crawl up or down the stairs. For instance, one such vehicle includes a plurality of wheels under the vehicle body, and a caterpillar track or belt disposed around the wheels. Further, hook claws are provided on the outer surface of the belt. As the belt is rotated, the hooks dig Into the surface of each step, thus damaging each step as the vehicle goes up or down the stair. Such vehicles are necessarily complicated, in part because of the plurality of wheels under the vehicle body.
There have been attempts to provide such a vehicle with a mechanism which maintains the seat in a horizontal position, since the vehicle body itself is inclined when going up or down a set of stairs. However, in order to maintain the seat in the horizontal state, the angle between the vehicle body and the seat must be maintained at the same angle as the inclination of stairs. Mechanisms which control the angle between the seat and the vehicle body are usually complicated structures that are expensive to manufacture.